Apparatus for flowing viscous liquids, including a by-pass between a pump outlet andthe liquid chamber



June 8, 1948. s PYLES 2,443,146

APPARATUS FOR FLOWING vIscoUs LIQUIDS INCLUDING A BY-PASS BETWEEN A PUMP OUTLET AND THE LIQUID CHAMBER Filed Sept. 17, 1945 H II, I? I:

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JNVENTOR.

Patented June 8, 1948 PATENT OF'Fl FOR FIJQWING WESGQU'S @IQHWS, .J'N-QLU NG -iA-.' Y-1PASS J3 i-A OUTLEZI AND THE LIQUJD CHAMBER "Georges. P-yles, Glendale, Calif.

,ibmplicatiomseptember 17, 19.45,. Serial.No..=6lfi,754

3"Clai'ms. 1 My invention .hasto do withran apparatus for flowing viscous or colloidal liquids, such as plastic solutions, onto "the surfaceswhere they are to be used.

been deemed necessary to brush the solutions onto thasnrface of use because. of the. impracticabi'lity of those efforts which have heretofore been made to force them by pressure througha hose and nozzle. Such attempts havemmven impracticable largely because, iif .such materials are subjected 'to any considerable air pressure, they tend toroll"in' emerging from the hose, 'due perhaps to air pockets causing back pressures, with the result that no uniformity of flow can be obtained, and, due to the characteristics of such materials, if low pressure is used, no adequate flow is obtained. Moreover, in handling such materials it is highly important to keep them free of exposure to air as far as possible since air exposure causes chemical reactions tending to clog the apparatus.

In other words, it has been found impossible with known apparatus to obtain desirable and practicable flowing conditions for such materials.

I have found that I am able to completely overcome the difliculties which have been experienced in this art by using as the storage for the solution a pressure pot in which pressure is exerted on the solution by a fluid-actuated piston. I use the pressure pot merely for forcing the solution into the intake of a pump which finally forces the solution through a delivery hose. I remove all excessive pressure by providing a constantly open adjustable return conduit from the pump to the pressure pot, which enables the pump to be operated even though the delivery valve of the hose is closed, without exerting excessive pressure on the material in the hose.

It is therefore among the objects of my invention to provide an apparatus for flowing viscous solutions without subjecting them to excessive pressures.

It is also an object to provide an apparatus wherein the solution is not exposed to air prior to emerging from the delivery hose.

More specifically it is an object to provide apparatus for such purpose utilizing, in combination. a pump, a pressure pot for delivery of the solution to the pump and means for returning excess material from the pump to the pressure pot.

My invention also contemplates a novel pressure pot construction for use in such assembly.

Other objects and advantages of my invention will appear from the following detailed-description of a, particular embodiment in which the, single "figure illustrates somewhat schematically an .JaDDarat-us-unit for-"carrying out the invention, the pressure pot orreservoir -elemen-t being shown in .medial section.

Referring-now-to the drawings 1 show at 5 a platform gmounted oncasters fi for portability. On the platform I support, as "by legs 8', a pressure pot-or reservoi-rgenerally-denoted ill and comprising-a cylinderll having a bottom end closure -l5--and a top closure ll; retained :in positionby screw-elampsl-fl. A pistonill is slidably mounted in the cylinder and divides the cylinder into a solution chamber and a pressure chamber 26, the solution chamber being variable in capacity in response to movement of the piston.

A conventional gear pump is shown in side elevation at supported on the platform as by base 3|, and a conventional air motor is supported on the platform as by base 36, the motor being operatively connected to the pump by a drive shaft 38. Air under pressure communicates with the pressure chamber through a conduit 40 and a T connection 4|, from an air pressure source not shown, a pressure gauge 43 being connected into the T. Gate valve means 45 controls admission of air into the apparatus from the source and. from one leg of the T and through a control valve 41, a flexible conduit 48 leads to the air motor to operate the latter in order to drive the pump.

From an outlet port 50 in the bottom of the pressure pot a conduit 5| leads to the inlet of the pump. The outlet of the pump is provided with a T fitting 52, one leg of which carries a pressure gauge 56 and a control valve 51, the latter leg having connected to it a final delivery hose 58 carrying at its end a suitable nozzle 59. From leg 60 of the T 52 and through a control valve 62, a return conduit 63 leads into the solution chamber 25 through fitting 65 mounted in the top wall of the pressure pot, and thence through a flexible hose 66 and port 61 through piston 20.

In operation, air enters chamber 25 through T fitting 4-] and at the same time enters the air motor through conduit 48, thus simultaneously forcing the piston downwardly in the cylinder to force solution from chamber 25 into the pump inlet and starting the pump by means of the air motor. The valve 62 may be set so that any desired pump pressure is delivered on the solution in hose 58 and this pressure will be at all times maintained uniform since any excess pressure is relieved by return of solution from the pump to the solution chamber. When the valve 51 is closed, as frequently takes place in use, as for instance when the user moves the nozzle from one spot to another, all the solution taken into the pump will be returned to the chamber 25, thus relieving the liquid in line 58 of any, pressure.

I claim: 7 1

1. Apparatus for efiecting pressure flow of viscous liquids comprising, in combination with a driven pump having a liquid inlet and a liquid outlet, a tank, a piston reciprocably mounted in the tank for movement to impose pressure upon liquid in a liquid chamber portion of the tank, means providing communication from the liquid chamber to the} pump inlet,

means acting upon the piston to move the same to impose pressure upon the liquid to force liquid from the liquid chamber through the pump inlet, and means establishing communication between the pump outlet and the liquid chamber through the piston.

2. Apparatus for effecting pressure flow of viscous liquids comprising, in combination with a driven pump having a liquid inlet and a liquid outlet, a tank, a piston reciprocably mounted in the tank and dividing, the tank into a liquid chamber and'a pressure chamber, means providing communication from the liquid chamber tothe pump inlet, means for introducing fluid under pressure into the pressure chamber Whereby to cause the piston to force liquid from the liquid chamber. into the pump inlet, and means establishing communication between the pump.

inlet and the liquid chamber through the pres sure chamber and piston including a flexible conduit extending through the pressure chamber.

3. Apparatus for effecting pressure flow of viscous liquids comprising, in combination with a source of fluid pressure, ,a tank, a piston reciprocably mounted in. thetankand dividing it into a pressure chamber and a' liquid chamber of variable capacity, means establishing communication between the source of fluid pressure and the pressure chamber to actuate the piston, a pump having its intake in communication with the liquid chamber, a flow line in communication with the pump outlet, means establishing return flow communication from the pump outlet to the liquid chamber through the pressure chamber and through the piston, and means responsive to Number Name Date, r 1,658,217 Winkley Feb/7, 1925 1,764,968 Mendenhall June 17,1930 1,801,414 Davis i A r; 21, 1931 1,893,738 Goodman n-. Jan. 10,1933 2,134,735 Reinhold Nov. 1, 1938 2,287,789 7 Drollet June 30, .l942 

